The present invention relates to a sheet coated with a powdery coating composition, and its production and use. More particularly, it relates to a sheet coated with a powdery coating composition, comprising a substrate and, a porous and continuous resin layer comprising particles of a powdery coating composition with space therebetween provided on the substrate, and its production and use particularly as an image-receiving sheet for a water based ink-jet recording.
Various recording systems have hitherto been known, and there has widely been used a water based ink-jet recording system for ejecting ink directly through a nozzle towards an image-receiving sheet, thereby to adhere ink and to record an image, recently.
This image-receiving sheet for a water based ink-jet recording has hitherto been formed by wet-coating a solution prepared by mixing a water-soluble or water-swelling resin, an inorganic pigment (such as silica) and other additives, on a substrate, drying the solution thereby to form a resin layer on the substrate, to disperse the inorganic pigment in the resin layer and to form a porous resin layer containing micropores therein. When the image-receiving sheet receives water based ink-jet ink, the ink is absorbed both in the micropores and resin thereby to form an image on the image-receiving sheet. In such way, a high-quality recording image could have hitherto been obtained by an ink-jet recording system using a specially prepared image-receiving sheet.
In such a specially prepared exclusive image-receiving sheet, however, an ink-receiving layer is formed by wet-coating a resin and other additives on a substrate, and hence, an environmental consideration is required on removal of the solvent. Furthermore, the resin to be used is limited as described above and the resulting image-receiving sheet is expensive because of many production processes and the use of an organic solvent.
The present inventors have intensively researched the production of an image-receiving sheet for an ink-jet recording by dry-coating of a powdery coating composition, not wet-coating. As a result, they have found that, it is possible to form, on a substrate, a porous and continuous resin layer comprising particles of a powdery coating composition and inorganic fine particles dispersed between the particles to form space at least in part between the particles of the powdery coating composition so that the particles of the powdery coating composition are apparently isolated at least in part from each other by the inorganic fine particles by mixing the powdery coating composition with the inorganic fine particles in a predetermined ratio to form a powdery mixture, coating the powdery mixture on the substrate, melting the coated powdery mixture by heating and fixing it.
The present inventors have found that such an image-receiving sheet for an ink-jet recording having a resin layer as an ink-receiving layer can be produced simply at low cost by using any resin with no restriction. Moreover, such an image-receiving sheet for an ink-jet recording is superior in permeability and absorbency of jet printing ink and a clear image having high density is formed by the image-receiving sheet for an ink-jet recording, thereby making it possible to obtain a high quality ink-jet recording image. Thus, the present invention has been accomplished.
Therefore, it is an object of the present invention to provide a sheet coated with a powdery coating composition whose resin layer on a substrate has a specific structure, a method for the production and use thereof, particularly an image-receiving sheet for an ink-jet recording.
Furthermore, the present inventors have found that it is possible to obtain an image-receiving sheet for an ink-jet recording, capable of forming a clearer and more accurate image having higher density, by forming on a substrate a porous and continuous resin layer composed of particles of a powdery coating composition and a first inorganic fine particles dispersed between the particles to form space at least in part between the particles of the powdery coating composition, and further forming a surface layer composed of a second inorganic fine particles on the resin layer. Thus, the present invention has been accomplished.
It is a further object of the invention, therefore, to provide an image-receiving sheet for an ink-jet recording, capable of forming a clear and accurate image having high density, which comprises a substrate and, a porous and continuous resin layer provided on the substrate, the resin layer comprising particles of a powdery coating composition and a first inorganic fine particles dispersed between the particles and forming space at least in part between the particles of the powdery coating composition, the sheet further comprising a surface layer comprising a second inorganic fine particles on the resin layer, and its production.
According to the present invention, there is provided a sheet coated with a powdery coating composition, comprising a substrate and a porous and continuous resin layer provided on the substrate, the resin layer comprising particles of the powdery coating composition having an average particle diameter of 0.1 to 30 xcexcm and inorganic fine particles having an average particle diameter of 1 nm to 1 xcexcm dispersed between the particles of the powdery coating composition and forming space at least in part between the particles of the powdery coating composition.
Such a sheet coated with a powdery coating composition of the invention can be suitably used as an image-receiving sheet for an ink-jet recording.
Such a sheet coated with a powdery coating composition can be obtained by mixing a powdery coating composition having an average particle diameter of 0.1 to 30 xcexcm with inorganic fine particles having an average particle diameter of 1 nm to 1 xcexcm to form a powdery mixture, dry-coating the powdery mixture on a substrate, melting the powdery coating composition by heating, and fixing the melted powdery coating composition on the substrate together with the inorganic fine particles to form a resin layer having at least in part space between the particles of the powdery coating composition, in accordance with the invention.
Further according to the invention, there is provided an image-receiving sheet for an ink-jet recording, comprising a resin layer having a thickness of 1 to 100 xcexcm and a surface layer comprising inorganic fine particles having an average particle diameter of 1 to 50 nm formed on the resin layer, the resin layer comprising particles of a powdery coating composition having an average particle diameter of 0.1 to 30 xcexcm and containing a resin and a colorant.
Such an image-receiving sheet for an ink-jet recording can be obtained by a method comprising the steps of dry-coating particles of a powdery coating composition having an average particle diameter of 0.1 to 30 xcexcm and containing a resin and a colorant, on a substrate to form a resin layer, forming a surface layer comprising inorganic fine particles having an average particle diameter of 1 to 50 nm on the resin layer, fixing the resin layer on the substrate, and fixing the surface layer on the resin layer.
Particularly, a preferred image-receiving sheet for an ink-jet recording according to the invention comprises a substrate and, a porous and continuous resin layer provided on the substrate, the resin layer comprising particles of a powdery coating composition having an average particle diameter of 0.1 to 30 xcexcm and containing a resin and a colorant, and a first inorganic fine particles having an average particle diameter of 1 nm to 1 xcexcm dispersed between the particles of the powdery coating composition to form at least in part space therebetween, the sheet further comprising a surface layer comprising a second inorganic fine particles having an average particle diameter of 1 to 50 nm on the resin layer.
Such an image-receiving sheet for an ink-jet recording can be obtained by mixing a powdery coating composition having an average particle diameter of 0.1 to 30 xcexcm, which contains a resin and a colorant, with a first inorganic fine particles having an average particle diameter of 1 nm to 1 xcexcm to form a powdery mixture, dry-coating the powdery mixture on a substrate to form a resin layer, and forming a surface layer comprising a second inorganic fine particles on the resin layer.